The present invention relates to a battery holder mechanism for holding a battery in a device such as an IC card which may be used as a game card, or in thin desk-top calculators, thin watches and the like.
An example of a device having a conventional battery holder mechanism as used in an IC card will be described with reference to FIGS. 1 to 3. As shown in FIG. 1, an IC card 1 has a package 2 which receives therein a semiconductor device (not shown) including thin semiconductor elements, electronic components, and a battery. The package 2 comprises a frame 3 and panels 4 adhesion bonded to the upper and lower sides of the frame 3 so as to provide covers. The frame 3 and panels 4 are made of an insulating material such as a synthetic resin. A battery receiving hole 5 is formed on the rear side of the package 2 so that a battery holder body 6 holding a battery, as shown in FIG. 2, can be inserted into the hole 5 by being pushed in the direction indicated by the arrow A shown in FIG. 1.
FIG. 2 is a plan view of the battery holder body 6 as received within the package 2. The battery holder body 6 is also made of a synthetic resin and holds a flat battery 10. When the battery holder body 6 is inserted into the receiving hole 5 of the frame 3, engagement pawls 6a on both sides of the battery holder body 6 engage with engagement recesses 3a of the frame 3 by springing outward into the recesses 3a by virtue of their resilience. The battery holder body 6 also has a circular-arc portion 6b extending in the circumferential direction of the battery 10, and a lower supporting projection 6c projecting radially inwardly from the lower side of the inner peripheral edge of the circular-arc portion 6b. The battery 10 is supported from below by the lower supporting projection 6c, as shown in FIG. 3 which shows the lower supporting projection 6c, the battery 10, and the related members in section.
The IC card 1 which has the above-described battery holder mechanism is used, for instance, by inserting it into a connector of a card reader (not shown), thereby electrically connecting the card.
An IC card having the conventional battery holder mechanism, however, encounters the following problem. Namely, with this machine, the battery 10 is simply placed on the lower supporting projection 6c of the battery holder body 6 and is therefore loosely supported. This arrangement is disadvantageous in that there is a risk of the battery 10 colliding with the upper panel 4 when the card 1 is turned upside down, creating a burden on the panel 4. In particular, if the card 1 happens to be dropped, the battery 10 can collide heavily against the panels 4, leading to destruction of the components of the card 1.